MAD1108 can they be used in HF mixers?

[neazoi]

Hi, I wonder if the MAD1108 can be used in HF mixer applications (<30MHz)?
Also do you expect the diodes inside the same package to be matched?
What other DIP options are there for mixing on HF?

I attach the datasheet

 

[betwixt]

The device is optimized for use in data line protection rather than high frequency. The diodes will not be well matched and they have a high Vf so you would probably need higher signal levels than if normal diodes were used. Their maximum Vf is 1.0V at 10mA, compare that with 0.4V for a Shottky device like the BAT85. The manufacturer doesn't provide a V/I graph as it wouldn't normally be important at low voltages in a protection circuit but I would guess it's performance would be poor. It may also suffer from cross coupling between diodes as it wouldn't normally be expected to conduct at HF. Overall - not a good choice.

If you are looking for DIP packages it might be better to look at active mixers, somethng like the SA602 which has a balanced mixer and oscillator in an 8-pin DIP package.

Brian.